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Cheap flights from Chicago (CHI) to Seattle (BFI)

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0 Children (2~11)
0 Infants (0~2)
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How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)

How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)
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How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)
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How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)
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Cheap flights from Chicago to Seattle in September , October 2026

18 Sep - 11 Oct $ 794.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates
17 Sep - 11 Oct $ 794.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates
24 Sep - 11 Oct $ 794.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates

Last minute flights from Chicago to Seattle

18 Sep - 01 Oct $ 888.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates
24 Sep - 01 Oct $ 888.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates
17 Sep - 01 Oct $ 888.00
CHI
Chicago
Frontier Airlines
2 STOPS
BFI
Seattle
BFI
Seattle
Frontier Airlines
2 STOPS
CHI
Chicago
Pick dates

One-way flights to Seattle from Chicago

6:30 AM - 4:05 PM
Air Excursions
2 Stops
12h 25m
CHI - BFI
$ 449
Kiwi
Pick dates
6:30 AM - 4:05 PM
Air Excursions
2 Stops
12h 25m
CHI - BFI
$ 449
Kiwi
Pick dates
6:30 AM - 4:05 PM
Air Excursions
2 Stops
12h 25m
CHI - BFI
$ 449
Kiwi
Pick dates

How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)

Related info for your journey
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How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.
How to find the cheapest flight from Chicago (CHI) to Seattle (BFI)
Some placeholder content for the first accordion panel. This panel is shown by default, thanks to the .show class.